1. Technical Field
The present disclosure relates to a plastic product manufacturing method and an all-electric injection-molding machine.
2. Description of Related Art
In recent years, with the increase in environmental awareness, there have been significant changes with respect to industrial equipment. An obvious example of this is processing equipment in the plastic molding industry, which has undergone a change from general hydraulic equipment to electric equipment with environmentally friendly aspects. As the name suggests, the power system of an all-electric injection-molding machine is driven by electric motors. That is, conventional hydraulic cylinders or pneumatic cylinders are replaced by servo motors or induction motors.
An all-electric injection-molding machine is fast, accurate, stable, quiet, energy saving, and clean, and so has been revolutionary in the area of plastic injection molding machines. All-electric injection-molding machines can be applied in various different fields, such as those related to consumer products and industrial supply products (e.g., silicone products, polyethylene terephthalate containers, vehicle parts, cosmetics containers, domestic containers, precision gears, etc.), as well as those related to precision injection products (e.g., semiconductor components, information and computer products, optical lenses, liquid crystal display light guide plates, integrated circuit cards, electronic material components, etc.). All-electric injection-molding machines also provide great benefits with respect to advanced micro-injection molding technology in the fields of biochemistry, medicine, microelectromechanical systems (MEMS), information technology (IT), optoelectronics, precision measurement components, etc.
In general, all-electric injection-molding machines involve central control (i.e., a high-level controller processes all procedures and gives orders to low-level drivers and motors). The infrastructure of an all-electric injection-molding machine is similar to that of a traditional hydraulic injection-molding machine. However, pressure and speed control of an all-electric injection-molding machine during an injection stage and a material storage stage need immediate feedback control. Moreover, the response to requests of an all-electric injection-molding machine is faster than in a hydraulic system. In addition to numerical display of a human-machine interface, the high-level controller of an all-electric injection-molding machine also includes procedure control, and squeezing speed control and command tracking control of pressure in each process. For example, the flowing speed and generated pressure of a melt plastic substance change rapidly, and so real-time computing capability of a high-level controller must be quite fast. Under such circumstances, the operation interval of a high-level controller cannot be very short, otherwise the injection quality of the overall system cannot be raised. In order to get a good injection product, it is necessary to rely on experienced technicians who spend a lot of time adjusting injection conditions of speed and pressure. Some academics have suggested the Taguchi method to get the best conditions. Therefore, use of an all-electric injection-molding machine entails significant technician involvement and material costs.